Len What is the difference between the backing plates and flanging? Thanks
Flanging tends to bend the metal while flanging keeps the metal flat. Flanging is easily done in metal that is bent and curved while flanging tends to distort a curved application. Flanging works ok on flat metal while the backing strip works good in just about all applications. Cutting your backing strip out of the same repair panels or from the original metal works great. The good thing about flanging is that you only have one seam the back side while the backing strip has two.
Originally Posted by Belair1955
If you use the backing strip it's best to PUNCH the holes rather than to drill them. Punching the holes gives you a much flatter panel so that your metal pieces lay flat together. A good hand punch works very well for both punching and flanging.